The present invention relates to the fabrication of reversible highlighting rotating element sheet material and to a reversible highlighting addressing method.
One of the largest expenditures in the area of education is that of textbooks and course materials. The market for both new and used textbooks and course materials extends through all levels of education, from elementary school to college and beyond to graduate and professional school. One of the most common reasons that educational material inevitably drops out of the new and used markets is due to a mainstay of studying techniques: the use of write-only conventional highlighters. As more advanced modes are created for conveying textual and graphical information, as with xe2x80x9creusable electric paper,xe2x80x9d it remains desirable to duplicate the advantages of the conventional highlighter while avoiding the drawbacks.
I.A.1. Conventional Highlighters
The conventional highlighter, or conventional highlighting implement, is generally a felt-tipped marker and is available commercially under the names HI-LITER (available from Avery Dennison, Pasadena, Calif.) and POCKET ACCENT (available from Sanford, Bellwood, Ill.), as well as others. The highlighting implement is used to apply a layer of transparent-colored ink to light-colored paper printed with conventional dark-colored ink. The transparent color of the highlighting ink is usually selected such that, when applied to the light-colored paper, a noticeable change in appearance occurs. Visually, text or graphics of a first dark color on a background of a first light color is altered to appear as text or graphics in a second dark color on background of a second light color. The first dark color corresponds to the color of the conventional ink used to print the text or graphics. Likewise, the first light color corresponds to the color of the paper on which the text or graphics was printed. Furthermore, the second dark color is a combination of the first dark color and the first transparent color of the highlighting ink. Usually, the first transparent color of the highlighting ink is chosen such that the first dark color appears visually identical to the second dark color. That is, the first dark color saturates the first transparent color. Conversely, the first transparent color of the highlighting ink is chosen such that there is a noticeable difference between the first light color and the second light color. However, it is also chosen such that there remains sufficient contrast between the second light color and the second dark color so that the text or graphics in a second dark color on a background of a second light color remain legible. By way of example, the first light color may be white, the first dark color may be black, and the first transparent color of the highlighting ink may be yellow, orange, pink, or other colors. In the example described above, the first transparent color of the highlighting ink saturates the white appearance of the first light-colored background.
As a write-only process, subsequent conventional highlights after a first conventional highlight are of decreasing usefulness when the goal of the user is to mark significant passages of text for later easy reference. A typical practice after a first conventional highlight is to select a highlighting ink of a second transparent color that saturates the first transparent color. For example, if the first transparent color is yellow, the first light color is white, and the first dark color is black, a second transparent ink that is orange-colored will generally saturate the yellow-colored appearance of the first conventional highlight. Following a second conventional highlight, again, there is decreasing usefulness in a third or fourth conventional highlight. Ultimately, the highlighted material is discarded, and a fresh set of materials that present text or graphics of a first dark color on a background of a first light color is generated for a first conventional highlight.
There also exist a class of so-called xe2x80x9cerasable highlighters.xe2x80x9d For example, U.S. Pat. No. 3,941,488, and U.S. Pat. No. 4,681,471 disclose kits consisting of markers and erasers where the marker disperses an ink, and the eraser disperses a corresponding reagent selected to remove or obliterate the dispersed ink without affecting the appearance of the underlying text and graphics. Both of the above disclosures, however, are based on a specific pairing between marking ink and erasing reagent, and are not generally suitable for all commercially available highlighters. U.S. Pat. No. 5,427,278 discloses a highlighting-ink remover designed to, obliterate water-based, non-pigmented dyes without affecting, again, the underlying text and graphics. Although the above technique is more suitable than the preceding two with respect to use with conventional highlighters, it is based upon the use of a liquid bleaching agent, and, hence, the quality of the paper or substrate can be affected following each use. Again, such a technique can be of decreasing usefulness after each highlight and removal.
In light of the foregoing, it remains desirable to fabricate textbooks and course materials that can accommodate reversible highlighting without affecting the quality of the underlying text, graphics, or substrate following each highlight and removal. Therefore, later users can reverse all of the existing highlighted aspects and then introduce new highlighted aspects to suit their own needs.
Rotating element sheet material has been disclosed in U.S. Pat. Nos. 4,126,854 and 4,143,103, both herein incorporated by reference, and generally comprises a substrate, an enabling fluid, and a class of rotatable elements. As discussed more below, rotating element sheet material has found a use as xe2x80x9creusable electric paper.xe2x80x9d FIG. 1 depicts an enlarged section of rotating element sheet material 18, including rotatable element 10, enabling fluid 12, cavity 14, and substrate 16. Observer 28 is also shown. Although FIG. 1 depicts a spherically shaped rotatable element and cavity, many other shapes will work and are consistent with the present invention. As disclosed in U.S. Pat. No. 5,389,945, herein incorporated by reference, the thickness of substrate 16 may be of the order of hundreds of microns, and the dimensions of rotatable element 10 and cavity 14 may be of the order of 10 to 100 microns.
In FIG. 1, substrate 16 is an elastomer material, such as silicone rubber, that accommodates both enabling fluid 12 and the class of rotatable elements within a cavity or cavities disposed throughout substrate 16. The cavity or cavities contain both enabling fluid 12 and the class of rotatable elements such that rotatable element 10 is in contact with enabling fluid 12 and at least one translational degree of freedom of rotatable element 10 is restricted. The contact between enabling fluid 12 and rotatable element 10 breaks a symmetry of rotatable element 10 and allows rotatable element 10 to be addressed. The state of broken symmetry of rotatable element 10, or addressing polarity, can be the establishment of an electric dipole about an axis of rotation. For example, it is well known that small particles in a dielectric liquid acquire an electrical charge that is related to the Zeta potential of the surface coating. Thus, an electric dipole can be established on a rotatable element in a dielectric liquid by the suitable choice of coatings applied to opposing surfaces of the rotatable element.
The use of rotating element sheet material 18 as xe2x80x9creusable electric paperxe2x80x9d is due to the fact that the rotatable elements are typically given a second broken symmetry, a multivalued aspect, correlated with the addressing polarity discussed above. That is, the above mentioned coatings may be chosen so as to respond to incident electromagnetic energy in distinguishable ways. Thus, the aspect of rotatable element 10 to observer 28 favorably situated can be controlled by an applied vector field.
For example, as disclosed in U.S. Pat. No. 4,126,854, hereinabove incorporated by reference, rotatable element 10 may comprise a black polyethylene generally spherical body with titanium oxide sputtered on one hemisphere, where the titanium oxide provides a light-colored aspect in one orientation. Such a rotatable element in a transparent dielectric liquid will exhibit the desired addressing polarity as well as the desired aspect.
A multivalued aspect in its simplest form is a two-valued aspect. When the aspect is the chromatic response to visible light, rotatable element 10 with a two-valued aspect can be referred to as a bichromal rotatable element. Such a rotatable element is generally fabricated by the union of two layers of material as described in U.S. Pat. No. 5,262,098, herein incorporated by reference.
FIGS. 2-4 depict rotatable element 10 with a two-valued aspect and an exemplary system that use such rotatable elements. In FIG. 2, rotatable element 10 is composed of first layer 20 and second layer 22 and is, by way of example again, a generally spherical body. The surface of first layer 20 has first coating 91 at a first Zeta potential, and the surface of second layer 22 has second coating 93 at a second Zeta potential. First coating 91 and second coating 93 are chosen such that, when in contact with a dielectric fluid (not shown), first coating 91 has a net positive electric charge with respect to second coating 93. This is depicted in FIG. 2 by the xe2x80x9c+xe2x80x9d and xe2x80x9cxe2x88x92xe2x80x9d symbols respectively. Furthermore, the combination of first coating 91 and the surface of first layer 20 is non-white-colored, indicated in FIG. 2 by hatching, and the combination of second coating 93 and the surface of second layer 22 is white-colored. One skilled in the art will appreciate that the material associated with first layer 20 and first coating 91 may be the same. Likewise, the material associated with second layer 22 and second coating 93 may be the same.
FIG. 3 depicts no-field set 30. No-field set 30 is a subset of randomly oriented rotatable elements in the vicinity of vector field 24 when vector field 24 has zero magnitude. Vector field 24 is an electric field. No-field set 30, thus, contains rotatable elements with arbitrary orientations with respect to each other. Therefore, observer 28 in the case of no-field set 30 registers views of the combination of second coating 93 and the surface of second layer 22, and first coating 91 and the surface of first layer 20 in an unordered sequence. Infralayer 26 forms the backdrop of the aspect. Infralayer 26 can consist of any type of material or aspect source, including but not limited to other rotatable elements or some material that presents a given aspect to observer 28.
FIG. 4 depicts first aspect set 32. First aspect set 32 is a subset of rotatable elements in the vicinity of vector field 24 when the magnitude of vector field 24 is nonzero and has the orientation indicated by arrow 25. In first aspect set 32, all of the rotatable elements orient themselves with respect to arrow 25 due to the electrostatic dipole present on each rotatable element 10. In contrast to no-field set 30, observer 28 in the case of first aspect set 32 registers a view of a set of rotatable elements ordered with the non-white-colored side up. Again, infralayer 26 forms the backdrop of the aspect. In FIG. 4, rotatable element 10, under the influence of applied vector field 24, orients itself with respect to vector field 24 due to the electric charges present as a result of first coating 91 and second coating 93, as depicted in FIG. 2.
One skilled in the art will appreciate that first aspect set 32 will maintain its aspect after applied vector field 24 is removed, in part due to the energy associated with the attraction between rotatable element 10 and the substrate structure, as, for example, cavity walls (not shown). This energy contributes, in part, to the switching characteristics and the memory capability of rotating element sheet material 18, as disclosed in U.S. Pat. No. 4,126,854, hereinabove incorporated by reference, and discussed in more detail below.
A rotatable element with multivalued aspect is generally fabricated as disclosed in U.S. Pat. No. 5,919,409, herein incorporated by reference. An exemplary rotatable element 10 with multivalued aspect is depicted in FIG. 5. Rotatable element 10 in FIG. 5 is composed of first layer 36, second layer 37 and third layer 38. First layer 36 and third layer 38 are transparent-clear to visible light and second layer 37 may be opaque or transparent-colored to visible light. The surface of third layer 38 has third coating 95 at a first Zeta potential, and the surface of first layer 36 has first coating 97 at a second Zeta potential such that third coating 95 has a net positive charge, xe2x80x9c+,xe2x80x9d with respect to first coating 97 when rotatable element 10 is in contact with a dielectric fluid (not shown). First coating 97 and third coating 95 are also chosen to be transparent-clear to visible light. As above, one skilled in the art will appreciate that the material associated with first layer 36 and first coating 97 may be the same. Likewise, the material associated with third layer 38 and third coating 95 may be the same.
Rotatable elements with multivalued aspects are generally utilized in rotating element sheet material that uses canted vector fields for addressing. A canted vector field is a field whose orientation vector in the vicinity of a subset of rotatable elements can be set so as to point in any direction in three-dimensional space. U.S. Pat. No. 5,717,515, herein incorporated by reference, discloses the use of canted vector fields in order to address rotatable elements. The use of canted vector fields with rotating element sheet material 18 allows complete freedom in addressing the orientation of a subset of rotatable elements, where the rotatable elements have the addressing polarity discussed above. An exemplary system that utilizes rotatable elements with three-valued aspects and a canted vector field for addressing is depicted in FIGS. 6-9.
In FIGS. 6-9, rotatable element 10 with a multivalued aspect is a xe2x80x9clight valve,xe2x80x9d as disclosed, for example, in U.S. Pat. No. 5,737,115, herein incorporated by reference and depicted in FIG. 5. FIGS. 6 and 7 depict first aspect set 72. In first aspect set 72, observer 28 registers a coherent view of the face of the disk of opaque or transparent-color second layer 37. Such a case corresponds to the case of a light valve that is xe2x80x9cclosed.xe2x80x9d First aspect set 72 maximally obstructs infralayer 26, where infralayer 26 can consist of any type of material or aspect source, including but not limited to other rotatable elements, or some material that presents a given aspect to observer 28. FIG. 6 is a side view indicating the relative positions of observer 28, first aspect set 72, and infralayer 26. FIG. 7 is an alternate view of first aspect set 72 from a top perspective. In FIG. 7, the symbol "THgr" indicates an arrow directed out of the plane of the figure. In FIGS. 6 and 7, rotatable element 10, under the influence of applied vector field 24, orients itself with respect to vector field 24 due to the electric charges present as a result of first coating 97 and third coating 95, as depicted in FIG. 5.
FIGS. 8 and 9 depict second aspect set 76 of the system introduced in FIGS. 5-7. In second aspect set 76, observer 28 registers a coherent view of the disk of opaque or transparent-color second layer 37 edge-on. In this case, infralayer 26 is minimally obstructed by the set of rotatable elements. Such a case corresponds to the case of a light valve that is xe2x80x9copen.xe2x80x9d FIG. 8 is a side view indicating the relative positions of observer 28, second aspect set 76, and infralayer 26. FIG. 9 is an alternate view of second aspect set 76 from a top perspective. Again, in FIGS. 8 and 9, rotatable element 10, under the influence of applied vector field 24, orients itself with respect to vector field 24 due to the electric charges present as a result of first coating 97 and third coating 95, as depicted in FIG. 5.
One skilled in the art will appreciate that first aspect set 72 and second aspect set 76 will maintain their orientation after applied vector field 24 is removed due to the energy associated with the attraction between rotatable element 10 and the substrate structure, as, for example, cavity walls (not shown). Again, this energy contributes, in part, to the switching characteristics and the memory capability of rotating element sheet material 18, as disclosed in U.S. Pat. No. 4,126,854, hereinabove incorporated by reference and discussed in more detail below.
In addition, one skilled in the art will appreciate that no-field set, first aspect set, and second aspect set discussed above in FIGS. 3, 4, and 6-9 can form the elements of a pixel, where vector field 24 can be manipulated on a pixel by pixel basis using an addressing scheme as discussed, for example, in U.S. Pat. No. 5,717,515, hereinabove incorporated by reference.
As discussed above, a useful property of rotating element sheet material 18 is the ability to maintain a given aspect after the applied vector field 24 for addressing is removed. This ability contributes, in part, to the switching characteristics and the memory capability of rotating element sheet material 18, as disclosed in U.S. Pat. No. 4,126,854, hereinabove incorporated by reference. This will be referred to as aspect stability. The mechanism for aspect stability in the above embodiments is generally the energy associated with the attraction between the rotatable elements and the substrate structure, or xe2x80x9cwork function.xe2x80x9d A host of factors influence the magnitude of the energy associated with the work function including, but not limited to: surface tension of enabling fluid in contact with first rotatable element or second rotatable element; the relative specific gravity of the rotatable elements to the enabling fluid; magnitude of charge on rotatable elements in contact with substrate structure, as, for example, cavity walls; relative electronic permittivity of enabling fluid and substrate structure; xe2x80x9cstickinessxe2x80x9d of substrate structure; and other residual fields that may be present. The applied vector field 24 for addressing must be strong enough to overcome the work function in order to cause an orientation change; furthermore, the work function must be strong enough to maintain this orientation in the absence of an applied vector field 24 for addressing.
FIG. 10 depicts a subsection of rotating element sheet material 18 that includes first rotatable element 80 and second rotatable element 90. Again, although FIG. 10 depicts spherically shaped rotatable elements and cavities, many other shapes will work and are consistent with the present invention, as, for example, cylindrically shaped rotatable elements and cavities. Also shown in FIG. 10 is enabling fluid 12, first cavity wall 82, second cavity wall 92, substrate 16, and surface 94. In the exemplary subsection of rotating element sheet material depicted in FIG. 10, first rotatable element 80 and second rotatable element 90 are fabricated so as to exhibit different work functions. For example, as disclosed in U.S. Pat. No. 5,739,801, herein incorporated by reference, a spherical rotatable element with a larger diameter and the same coatings as a spherical rotatable element with a smaller diameter can be shown to exhibit a higher work function. In FIG. 10, it is the interaction between first rotatable element 80 and first cavity wall 82 that gives rise to first work function. Likewise, it is the interaction between second rotatable element 90 and second cavity wall 92 that gives rise to second work function.
FIG. 11 depicts an exemplary graph of number 112, N, of rotatable elements that change orientation as a function of applied vector field 24, V, for rotating element sheet material 18 of FIG. 10 including a plurality of first rotatable elements 80 and a plurality of second rotatable elements 90. First work function 124, Vw1, corresponds to the magnitude of applied vector field 24 when the number of first rotatable elements 80 and second rotatable elements 90 that change orientation has reached first saturation level 116 plus second saturation level 114, Ns1+Ns2, corresponding to the orientation change of all first rotatable elements 80 and second rotatable elements 90 under the influence of applied vector field 24. Likewise, second work function 122, Vw2 corresponds to the magnitude of applied vector field 24 when the number of second rotatable elements 90 that change orientation has reached second saturation level 114, Ns2, corresponding to the orientation change of all second rotatable elements 90 only under the influence of applied vector field 24.
The process of addressing first rotatable elements 80 or second rotatable elements 90 only is depicted in FIGS. 12-14 and summarized below in Table 1.
As disclosed, for example, in U.S. Pat. No. 5,739,801, herein incorporated by reference, the process of changing the orientation of first rotatable elements 80 only from the orientation depicted in FIG. 10 involves a two-step process. The first step is indicated in FIG. 12. In FIG. 12, vector field 24 is applied in the direction of arrow 100 at first work function 124. This causes all of first rotatable elements 80 and second rotatable elements 90 to change orientation so that their addressing polarity aligns with the direction of the applied vector field 24. This is indicated in FIG. 12. In the context of the xe2x80x9clight-valvexe2x80x9d rotatable element discussed earlier, such an orientation corresponds to xe2x80x9cclosedxe2x80x9d valves.
In the second step of the two-step process, vector field 24 is applied in the direction of transverse arrow 110 at second work function 122. This causes all of second rotatable elements 90 to change orientation so that their addressing polarity aligns with the direction of the applied vector field 24. This is depicted in FIG. 13. The purpose of the second step is to change the orientation of the second rotatable elements 90 back to the xe2x80x9copenxe2x80x9d orientation. This will be referred to as xe2x80x9chighlight-erasingxe2x80x9d the aspect associated with the second rotatable elements 90.
Likewise, the process of changing the orientation of second rotatable elements 90 only from the orientation depicted in FIG. 10 is depicted in FIG. 14. Second work function 122 is applied in the direction of arrow 100 in order to change the orientation of second rotatable elements 90 only. This causes all of second rotatable elements 90 to change orientation so that their addressing polarity aligns with the direction of the applied vector field 24. In FIG. 14, first rotatable element 80 that is initially in an xe2x80x9copenxe2x80x9d orientation remains in an open orientation.
In this way, one or the other of the rotatable elements can be selectively oriented for viewing by favorably situated observer 28.
The method of selectively orienting first rotatable element 80 or second rotatable element 90 only is surnmarized below in Table 1. In Table 1, the columns are divided according to applied vector field 24 at first work function 124 or applied vector field 24 at second work function 122, and the columns are further subdivided according to whether the orientation of vector field 24 is in the general direction of observer 28, indicated by the symbol "THgr" and corresponding to the direction of arrow 100, or whether it is generally transverse to the direction of observer 28, indicated by the symbolxe2x86x92 and corresponding to the direction of transverse arrow 110. The letter xe2x80x9cYxe2x80x9d indicates that an applied field of magnitude suitable to overcome the appropriate work function is present in that particular orientation, and the letter xe2x80x9cNxe2x80x9d indicates that an applied field of magnitude not suitable to overcome the appropriate work function is present in that particular orientation. An additional column that indicates the number of steps necessary to obtain the desired aspect from a previous different aspect is also indicated. The row labeled xe2x80x9cFirst Aspectxe2x80x9d corresponds to the aspect and orientation depicted in FIG. 13, and the row labeled xe2x80x9cSecond Aspectxe2x80x9d corresponds to the aspect and orientation depicted in FIG. 14. The use of xe2x80x9cY-1stxe2x80x9d indicates the first step of a two-step process, and the use of xe2x80x9cY-2ndxe2x80x9d indicates the second step of a two-step process. For both rows, the starting orientation is that orientation depicted in FIG. 10.
A system for introducing a canted vector field in the direction of transverse arrow 110 for erasing purposes has been described, for example, in U.S. Pat. No. 5,708,525, herein incorporated by reference. FIG. 15 depicts selective erasing system 180 that can be used to introduce vector field 24 in the direction of transverse arrow 110 through a subsection of rotating element sheet material 18. In FIG. 15, selective erasing system 180 contains potential drop implement 182. As depicted in FIG. 15, one side of potential drop implement 182 has a magnitude equal to first potential 181, V1, and the opposite side of potential drop implement 182 has a magnitude equal to second potential 183, V2. Thus, potential drop implement 182 introduces vector field 24 throughout section 178 of the substrate of rotating element sheet material 18 in the direction of transverse arrow 110. Thus, by bringing selective erasing system 180 near surface 94 of rotating element sheet material 18, an erasing field is selectively introduced. The potential drop implement 182 is preferably located at the distal end of selective erasing system 180, where one side of distal end of selective erasing system 180 is determined by the location of first potential 181 and the opposite side of distal end of selective erasing system 180 is determined by the location of second potential 183.
Another erasing system is depicted in FIG. 16 and is also disclosed in U.S. Pat. No. 5,708,525, hereinabove incorporated by reference. In FIG. 16, positive electrode 184 and negative electrode 185 are dispersed throughout rotating element sheet material 18. The view depicted in FIG. 16 is a top perspective of rotating element sheet material 18. The dotted rectangular outline depicts rotating element sheet material 18. Positive electrode 184 and negative electrode 185 protrude outside of rotating element sheet material 18, and extend within rotating element sheet material 18 beneath surface 94 in the example depicted in FIG. 16. The magnitude of vector field 24 is given by the potential difference, V, between positive electrode 184 and negative electrode 185. The symbol xe2x80x9c+xe2x80x9d indicates a positive polarity and the symbol xe2x80x9cxe2x88x92xe2x80x9d indicates a negative polarity. Again, vector field 24 of magnitude V will be oriented in the direction of transverse arrow 110 or transverse arrow 111. Thus, by introducing a suitable potential difference between positive electrode 184 and negative electrode 185 the entire sheet of rotating element sheet material 18 can be bulk-erased.
In what follows, xe2x80x9csubstantive aspectxe2x80x9d is the aspect addressed at first work function 124, excluding those aspects that can be addressed at lower values of the applied vector field 24, and hence can be erased at lower values of the applied vector field 24. For example, addressing system 190, disclosed in U.S. Pat. No. 5,389,945, herein incorporated by reference, and depicted in FIG. 17 can be a horizontal bar or wand which travels down surface 94 of rotating element sheet material 18 in the direction of arrow 130 and addresses all first rotatable elements 80 to create substantive aspect 160. The exemplary rotating element sheet material 18 of FIG. 10 is rotating element sheet material 18 of this discussion. Bottom surface 192, which may comprise electrodes, interacts with addressing system 190, which rides along top surface 94 of rotating element sheet material 18, to introduce the appropriate vector field 24 at the appropriate location across addressing system 190. One skilled in the art will appreciate, however, that other addressing systems are also possible. Again, the view in FIG. 17 is from a top perspective.
In addition to addressing all of the first rotatable elements 80, as described above, all of the second rotatable elements 90 will also be highlight-addressed by the device depicted in FIG. 17 and also as depicted in FIG. 12. Thus, in order to orient second rotatable elements 90 such that they again present a transparent-clear aspect to observer 28, rotating element sheet material 18 can be highlight-erased at second work function 122. Either of the erasure systems presented in FIGS. 15 or 16 can be used to introduce a suitable highlight-erasing field.
Accordingly, a first embodiment of the present invention comprises a system of rotating element sheet material with reversible highlighting and a highlighting implement, where the rotating element sheet material with reversible highlighting is fabricated using two pluralities of rotatable elements. One plurality of rotatable elements is addressed to present a first aspect associated with substantive aspect, and the second plurality of rotatable elements is addressed to present a second aspect associated with reversible highlighting. The highlighting implement is configured to selectively orient the second rotatable elements only using a first vector field.
A second embodiment of the present invention comprises a system of rotating element sheet material with reversible highlighting and a highlighting implement, where the rotating element sheet material with reversible highlighting is fabricated using three pluralities of rotatable elements, where one plurality of rotatable elements is addressed to present a first aspect associated with substantive aspect, the second plurality of rotatable elements is addressed to present a second aspect associated with a first reversible highlighting, and the second and third rotatable elements together are addressed to present a third aspect associated with a second reversible highlighting. The highlighting implement is configured to either selectively orient the second rotatable elements only using a first vector field in a first direction, or selectively orient both the second rotatable elements and the third rotatable elements using a second vector field in a first direction.
Another embodiment of the present invention comprises the first embodiment system described above, further comprising an erasing implement, where the erasing implement is configured to selectively orient the second rotatable elements only using a second vector field.
A further embodiment of the present invention comprises the second embodiment system described above, further comprising an erasing implement, where the erasing implement is configured to either selectively orient the second rotatable elements only using the first vector field in a second direction or selectively orient both the second rotatable elements and the third rotatable elements using the second vector field in a second direction.
Further, in another embodiment of the present invention, a kit comprises the first embodiment system described above, an erasing implement, and a binder, where the erasing implement is configured to selectively orient the second rotatable elements only using a second vector field, and the binder is configured to accommodate the first embodiment system and the erasing implement.
Further still, in another embodiment of the present invention, a kit comprises the second embodiment system described above, an erasing implement, and a binder, where the erasing implement is configured to either selectively orient the second rotatable elements only using the first vector field in a second direction or selectively orient both the second rotatable elements and the third rotatable elements using the second vector field in a second direction, and the binder is configured to accommodate the second embodiment system and the erasing implement.
A first embodiment of a method of use consistent with the present invention comprises: providing the first embodiment system above; providing an erasing implement, where the erasing implement is configured to selectively orient the second rotatable elements only using a second vector field; applying the highlighting implement to a first region of the rotating element sheet material with reversible highlighting to selectively orient the second rotatable elements only; and applying the erasing implement to a portion of the first region of the rotating element sheet material with reversible highlighting to selectively orient the second rotatable elements only.
A second embodiment of a method of use consistent with the present invention comprises: providing the second embodiment system above; providing an erasing implement, where the erasing implement is configured to either selectively orient the second rotatable elements only using the first vector field in a second direction or selectively orient both the second rotatable elements and the third rotatable elements using the second vector field in a second direction; applying the highlighting implement to a first region of the rotating element sheet material with reversible highlighting to selectively orient the second rotatable elements only, or both the second rotatable elements and the third rotatable elements; and applying the erasing implement to a portion of the first region of the rotating element sheet material with reversible highlighting to selectively orient the second rotatable elements only, or both the second rotatable elements and the third rotatable elements.
Additional features and advantages of the invention will be set forth in the description that follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the process and apparatus particularly pointed out in the written description and claims herein as well as the appended drawings.